CBA's IT spend was just shy of $2 billion

The Commonwealth Bank's information technology expenses for the 2017 full year nudged the $2 billion mark, its largest IT spend on record.

CBA today released its annual results amidst the controversy swirling over its alleged breaches of money laundering and terrorism financing obligations.

The bank's 2017 IT spend was boosted by a one-off $393 million write-off for accelerated software amortisation in the first half.

This helped push its IT expenses up 31 percent from $1.5 billion to $1.94 billion year-on-year.

The write-off stemmed from a decision to speed up the amortisation of some of its older software assets following a review of its digital and direct banking capitalised software assets last December.

Speeding up amortisation – the spreading out of payments over multiple periods – of technology assets gives smaller pieces of software shorter and more useful lives.

It's a position other financial firms including Westpac, ANZ Bank, and IAG have taken in recent years.

CBA has not provided details on which specific software assets were amortised.

Over the past seven years CBA's information technology expenses have sat around $1.2 billion to $1.3 billion. The bank started breaking out its IT expenses in its financial results in 2011.

Its net profit for the full 2017 year grew 4 percent to reach $9.9 billion.